The invention relates to apparatus for removing pulverized particles or other type of particles carried along in a stream of gas, comprising a substantially cylindrical housing having a first portion provided with a tangentially directed inlet for the stream of gas to be purified, means for flushing the inner wall of the housing located in an annular zone which extends tranversely of the centerline of the housing and means for permitting the gas stream to exit. The housing is also provided with an eduction pipe which exits outside the housing in such a manner that the stream of gas to be purified flows through an axial track inside the housing. A similar scrubber in a particular embodiment is shown from U.S. Pat. No. 2,696,275 according to which the stream of gas is injected into a number of cyclone paths via a stationary blade rim and then passes along a moistened inner wall, after which the scrubbed stream of gas is removed upward through the eduction pipe.
One problem which arises in scrubbers is that some wall portions inside the housing are moistened occasionally as a result of local turbulence, so that there is a precipitation or deposit of the particles present or of the dissolved material. These deposits, also known as scruffs, may be the cause of pollution or of bacterial growth as a result of which the sanitary character of the scrubber is lost. The occurrence of such problems is particularly promoted by the turbulence of the stream of gas inside the housing.